System and method of electrical distribution.



P. H. THOMAS. SYSTEM AND METHOD OF ELECTRICAL DISTRIBUTION. APPLICATION FILED DBO. s, 1906.

968,896; Patented Aug. 30, 19.10.

w-u a c m 1/ VIZ-V20 4 11) 11 M A 3151141 tlll'ozucl r I v I M,

UNITED STATES pgrnntr OFFICE.

PERCY H. THOMAS, OF MONTCLAIR, NEW JERSEY, ASSIGNOR TO COOPER HEWITT ELECTRIC COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

SYSTEM AND METHOD OF ELECTRICAL DISTRIBUTION.

Specification of Letters Patent.

Patented Aug. 30, 1910.

Application filed December 8, 1806. Serial No. 346,817.

" Montclair, county of Essex, State of New Jersey, have invented certain new and useful Improvements in Systems and Methods of ElectricalDistribution, of which the following is a specification.

My invention relates to certain new and useful improvements in apparatus and methods for maintaining an approximately uniform su ply of energy to a consumption circuit, wiere the energy is derived from a source of varying electromotive force, em-

ployed in connection with storage batteries msuch manner that the latter are continuously connected with the consumption circuit and with the source of supply so as to act as a receiver of energy, receiving and giving off energy according to the variations ofthe source and of the demands of the consum tion circuit.

y invention is particularly applicable where the variations of the source are extremely wide, as in the case of an alternating source used in connection with a converter or rectifier, or where .the nature of the use is such that even small fluctuations of voltage orcurrent in the consumption circuit would be very disadvantageous, as in the case of telephone systems.

The object of my invention is to minimize fluctuations and to approximate uniform constant voltage in the consumption circuit, as nearly as may be desired.

. In the specific embodiment of my invention, shown in the drawings, I effect the de sired result by adding a'reactance in the path of flow of current from the storage attery to the consumption circuit and, beyond such reaetanee, a shuntconnection acro s s the circuit, of such a character as to afford a "shunt path for fluctuations in the consumption circuit. The reactance is an inductance and the shunt path for the fluetuations is a noninductive resistance or, if desired, it may be a second storage battery similar to that first mentioned.

In the drawings the figure is a diagrammatic view of my apparatus for this purpose.

The converter or rectifier 1, having a negative electrode 2 and positive electrodes 3 and 4, is sup lied with current from the divided secom cry 5 of a transformer, connected with any suit-able source of alternating current 16. The apparatus indicated in the drawing is a single phase, but invention applies equally to ,polyphase and other sources of varying electromotive force. The converter isoperatively connected with astorage battery 6, which is connected across t e two sides 7 and 8 of the supply circuit. The conductor 7 extends from the negative electrode 2, of the converter, and is connected by conductor 7 to one terminal of the battery 6. The conductor 8 extends from an intermediate point of the divided secondary 5, and is connected b conductor 8 to the other terminal of the attery.

' The inductance 9 is arranged in the conductor 7 leading from the negative electrode for the purpose of maintaining the currentand thereby maintaining the ronverier in conducting condition. The current from the secondary flows through the converter in one direction only, entering the same alternately, first from one positive and then from the other. This gives a uni-directional current varyin in value from zero to the maximum. T e inductance 9 seems to smooth out these fluctuations to a considerable extent and to cause a, more uniform flow of current. in the converter, in the consumption circuit and in the storage battery connected across the same, but I find that an enormous inductance at 9 is necessary to smooth out the current sufiiciently for the class of uses first above referred to, and my present invention contemplates an arrangement whereby a much smaller inductance will produce a more satisfactory result. I accomplish this by making the device 9 of moderate inductance and providing a second inductance 10 in the line beyond the point where the storage battery (6) is bridged across the same. This second inductance serves to further smooth out the fluctuations of current passing to the line, but the use of such second iiu uctancc 10 has some tendency to produce a constant current effect in the line. This is undesirable for tho-[purposes referred to, which require a. uni orm volt-age. This constant currenttendency may be compensated for and corrected to a considerable extent. by the use oi a shunt rcsistaucc ll across the circuit at apoint beyond the inductance 10. This resistance furnishes a noninductive path for current fluctuations and operates to hunt the same the fluctuations may be emplo across the line, thereby tending to pieverit the constant current tendency of inductance coils 9 and from producing improper or undesired operation of thetelephone instruments or other translating devices employed on the consumptioncircuit.

While the divided inductance is of considerable efiiciency in connection with the shunt resistance, I prefer to employ it in connection with a yet more efficient arrange energy, or, if large storage capacity is not' required, both batteries may be made of small size cells, or battery 6 may be made up of cells of lar e storage capacity and bat tery 12 of cel s of small storage capaclty, but in the latter case, of course, the number of cells must be the same or in any event the average voltage across 12 must be equal to the average voltage across 6.

If desired the system may be provided both with the resistance 11 and w1th battery 12, as shown in the drawings. In such case either or both of theseshunt paths for ed. For instance, the resistance 11 m thrown in by switch 13, while battery12. is cut out by switch 14 for purposes of repair or renewal.

In operation of the system the inductance 10 in the'path of flow of current from the storage battery 6 tothe consumption circuit serves to steady and maintain the flow in that direction. Fluctuations in the con'sump-- of resistance tion circuit due to chan therein, particularly the a rupt fluctuations of tele hone transmitters, cannot readily travel )ack through the inductance 10 to shunt across the battery 6, the inductance acting as a choke coil to prevent this; In my system the noninductive resistance 11 and the battery 12 furnish paths of low impedance for such fluctuations or tendencies to fluctuate. By those means difiiculties re sultmg from fluctuationa,-whether originating in the source of supply or in the consumption' circuit, are completely obviated; that is to say, the objectionable fluctuations from the source are completely smoothed out, while the useful fluctuations due to changes of resistance or of eleetromotive force originating in the consumption circuit,

adapted to store electrical energy and to restore the same ata critical electrical pressure, a reactance in the path of current flow of said storage device, and a noninductive shunt containing a source of electromotivw force counter to that of the source, bridged across the circuit beyond said inductance, for the purpose described. i

2. A 'rcuit, a'source oi alternating elec-- tromotive force, a vapor rectifier, and a storage battery bridged across the circuit, in. combination with an inductance in the path of flow of current of said storage battery and a second storage battery beyond said second inductance in parallel with said first mentioned battery and of substantially the same average voltage across the terminals. 1 3. A circuit, a source of alternating electromotive force, a vapor rectifier, and in ductance in the lead from the negative electrode of said rectifier, and a storage battery 7 bridged across the circuit beyond said inductance, in combination with a second inductance in the path of flow of current of said stora battery, and asecond storage battery yond said inductance in arallel with said. first mentioned battery an of substantially the same'average voltage across the terminals. 1

signed at New York in the county of New Yor and State of New York, this 5th day of December A. D. 1906.

PERCY H. THOMAS. Witnesses:

WM. III-CARL, Tnos. Brown. 

